Events: honor NGX_USE_GREEDY_EVENT when kqueue support is enabled.

Currently this flag is needed for epoll and rtsig, and though these methods
usually present on different platforms than kqueue, nginx can be compiled to
support all of them.

src/os/unix/ngx_readv_chain.c

@@ -136,7 +136,7 @@ ngx_readv_chain(ngx_connection_t *c, ngx_chain_t *chain)
                 return n;
             }
 
-            if (n < size) {
+            if (n < size && !(ngx_event_flags & NGX_USE_GREEDY_EVENT)) {
                 rev->ready = 0;
             }
 

src/os/unix/ngx_recv.c

@@ -87,7 +87,9 @@ ngx_unix_recv(ngx_connection_t *c, u_char *buf, size_t size)
                 return n;
             }
 
-            if ((size_t) n < size) {
+            if ((size_t) n < size
+                && !(ngx_event_flags & NGX_USE_GREEDY_EVENT))
+            {
                 rev->ready = 0;
             }